In one such known exhaust gas extraction apparatus (cf. Brochure of the Company Blaschke GmbH, D-86405 Meitingen, "`Air Track` Abgas-Absaug-System") the carriage can move freely. The known exhaust gas extraction apparatus serves to extract exhaust gases from commercial vehicles in operational and parking sheds in fire stations, ambulance stations and other operational areas. When the vehicle is stationary the extraction hose is clamped on to the exhaust of the vehicle by means of the extraction socket. When starting and driving off the vehicle, the extraction socket initially stays on the exhaust, so that the exhaust gases are sucked off and do not get into the vehicle shed. As the vehicle drives off the extraction hose is pulled along by the exhaust and draws the carriage behind it. The connecting hose is extended elastically. A control cam or the like is arranged at a predetermined point on the running rail and effects the release of the extraction socket as soon as the exhaust of the departing vehicle has passed the exit door and is located outside the vehicle shed. However, when the extraction socket is released from the exhaust, there is no longer any pull on the extraction hose and the carriage is pulled back by the elastically tensioned connecting hose. The carriage also pulls with it the extraction hose and the extraction socket connected thereto, which can result in injury to persons. Moreover the extraction hose and the extraction socket come to rest a long way from the door region. This has the disadvantage that, on return of the vehicle, the driver has firstly to pull the extraction socket and the extraction hose back to the door region. Since this is inconvenient, what happens is that the driver moves his vehicle so far back into the vehicle shed that the exhaust is near to the extraction hose, so that he then only has to lift the extraction socket and clamp it on to the exhaust. However this has the disadvantage that exhaust gases get into the vehicle shed.